Light-emitting diodes wherein a chip is disposed near the tip of a pair of metal leads and this chip is enclosed by a resin shell are generally known as light-emitting devices comprising LED chips. The LED chips are usually disposed inside a cup that is made by press molding at the tip of the metal leads. The cup has the effect of directing upward the light from the light-emitting element. The curved surface at the top of the resin shell has a sufficient curvature and acts as a lens for condensing the light that has been directed upward by the cup, or the light that comes directly from the light-emitting elements, at the top of the resin.
Another known example is a structure wherein a light-emitting element is disposed inside a container and a separately formed lens member is anchored to the top surface of the container in order to condense the light from the light-emitting element (JP (Kokai) [Unexamined Japanese Patent Publication] 2003-124,525).
By means of these examples, the shape and position of the lens is fixed and the focal point distance and other parameters that determine the condensed state cannot be changed.
On the other hand, it is known that the focal point distance of the lens of optical systems other than light-emitting devices, for instance, cameras and other optical systems being sold, is not fixed and the focal point distance and other optical parameters can be changed as needed. There are lens systems comprising optical systems wherein the lens is mechanically moved (JP (Kokai) [Unexamined Japanese Patent Publication] 2004-72,572; JP (Kokai) [Unexamined Japanese Patent Publication] 2004-104,423; and JP (Kokai) [Unexamined Japanese Patent Publication] 2004-129,495) and those wherein the lens uses a liquid (JP (Kohyo) [National Publication of International Patent Application] 2001-519,539; and JP (Kohyo) [National Publication of International Patent Application] 2002-540,464).
Light-emitting diodes and other light-emitting devices have recently been used for various types of lighting. It is preferred that the condensed state of light from the light-emitting element can be changed in accordance with specific applications, such as auxiliary light for a camera AF (autofocus) or for illumination.
Nevertheless, there is a problem when the light-emitting device and the device for adjusting the condensed state are separate parts, they are not convenient to handle, and they are difficult to adjust in order to produce with good precision the desired condensed state.
Therefore, the object of the present invention is to provide a light-emitting device comprising a condensation means, which is small and easy to handle, and with which it is possible to easily adjust the condensed state of the light-emitting device with good precision, and a method for producing the same.